Hi John,
First of all please make sure to click on "Lisence this software" when you have prompt for the same. then provide the email address on which you have purchased the subscription.if you have it already captured to the trial one you can click on "Not my Adobe ID" and change it.
Also check http://helpx.adobe.com/x-productkb/policy-pricing/activation-network-i ssues.html for any network issues if you are using right Adobe ID.
Thanks
Kapil Malik